Estratégias ômicas para o estudo da fisiologia reprodutiva em ovinos: uma análise sobre embriões e corpo-lúteo.

Abstract

The study 1 was performed to describe the protein profile of sheep embryos produced in vivo during the preimplantation period. Ten ewes were subjected to hormonal superovulation treatment and laparoscopic insemination. After 5-6 days of ovulation, the ewes were slaughtered and the embryos were recovered. Embryonic proteins were identified with nano-HPLC-coupled mass spectrometry and evaluated using four search databases (PEAKS, Proteome Discoverer software (PD), SearchGUI software, PepExplorer). We identified 667 proteins from 54 embryos (morula and blastocyst). The biological process of proteins were mainly related to cellular process (30%) and regulation (25%). Most proteins were located in the nucleus (17%) and cytoplasm (14%), and molecular functions were mainly related to binding (50%) and catalytic activity (27%). Analysis of the embryonic protein database revealed 49 enriched functional clusters based on gene and database ontology (KEGG, Up_Keywords, INTERPRO, SMART). Among these 49 clusters, were found clusters with potential association with embryo physiology. By grouping this large number of proteins according to their roles and biochemical attributes, we have established a comprehensive scenario to support our understanding of the physiology of the sheep embryo. The study 2 aimed to evaluate the corpus luteum lipid changes in sheep after superovulation treatment using MALDI-TOF-MS. A total of 2558 peaks detected (71.1/sample) were used for statistical analysis. In multivariate analysis, the orthogonal partial least squares discriminant analysis (OPLS-DA) revealed good discrimination potential between the superovulated and synchronized group. In Projecting Variable Importance (VIP) for lipid identification, PLS-DA generated a list of 13 ions (VIP>1) that represented potential altered lipids between groups. Lipids with a VIP score greater than 1.3 were identified as phosphatidylethanolamine PE (40: 6) (m/z 774.526), glycerophospholipids [PE (40:8) or PC (37:8)] (m/z 788.5125), glycerophospholipids [PE (36:8) or PC (33:8)] (m/z 732.4695), hexylheptanoate (m/z 621.2155), multiflorin A (m/z 659.174), phosphatidyl glycerophosphate PGP (i-13: 0 (19:0) (m/z 820.5), glycerophospholipid [PE (40:6) or PC (37:6)], o-glucuronide and phosphatidylcholine PC (34:5). Among these lipids, hexyl-heptanoate, multiflorin A, [PE (40:6) or PC (37:6)] and o-glucuronide were more expressed in the synchronized group, while PE (40: 6), [PE (40:8) or PC (37: 8)], [PE (36: 8) or PC (33: 8)], PGP (i-13:0 / i-19:0) and PC (34: 5) were more expressed in the superovulated group. In conclusion, the superovulatory treatments with FSH caused changes related to the lipid regulation in the ovine CL. These changes may be mainly involved with possible mitochondrial changes and increased progesterone production after superovulation treatments.